Arsenic in rice linked to genetic damage

In the last few years, rice in several regions around the world has been found to have high levels of arsenic - which has been linked to elevated genetic damage in humans.

A partnership between the University of Manchester and the CSIR-Indian Institute of Chemical Biology in Kolkata has proven a link between high arsenic levels in rice and chromosomal damage, as measured by micronuclei in urothelial cells in humans who eat rice as a staple.

Researchers studying people in rural West Bengal found that 0.2 mg/kg of arsenic was the magic number: those eating rice with a higher concentration of arsenic showed higher frequencies of micronuclei than those consuming rice with a lower concentration.

Micronuclei frequency is a telltale sign of chromosomal damage, and has been linked by other researchers to cancer.

The authors say their work raises considerable concerns about the health impacts of consuming high-arsenic rice as a staple, particularly among people with relatively poor nutritional status.

“Although concerns about arsenic in rice have been raised for some time now, to our knowledge, this is the first time a link between consumption of arsenic-bearing rice and genetic damage has been demonstrated. As such, it vindicates increasing concerns expressed by the European Food Safety Authority and others about the adequacy of regulation of arsenic in rice,” said Professor David Polya, who lead the Manchester research team.

“In the absence of contamination, rice is an easily stored food that provides essential energy, vitamins and fibre to billions of people around the world, but a small proportion of rice contains arsenic at concentrations at which we have observed significant genetic damage in people who consume it as a staple food. We hope that our work will encourage efforts to introduce regulatory standards for arsenic in food, and particularly in rice, which are more consistent and protective of human health.”

The study, ‘High arsenic rice is associated with elevated genotoxic effects in humans’, was published in Nature Publishing Group’s Scientific Reports as an open-access article.